US3653138A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Contrasting background display
Assignee: 3M Co
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Filing: 1970-04-13
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Granted: 1972-04-04
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Expires: 1990-04-13
Abstract
Abstract Contrasting background for display of letters, numbers, or other indicia is provided by using a sheet of louvered material in which thin parallel opaque louvers are set in a transparent matrix at an angle to the faces of the sheet. Light is made to pass through the louvered sheet generally parallel to the louvers at an angle to the faces of the sheet to display indicia defined by a differential pattern of light diffusive and transparent areas. The light diffusive areas direct a portion of the incident light to an observer while the louvers are seen in contrast through the transparent areas.
Inventors
- 👤 Irvin J Cooper
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 13:04
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/02; G02B27/022; G02B27/024; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1335; G02F1/133524; G09; G09F; G09F13/00; G09F13/04; G09F13/06
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
175 words
A display device comprising: a sheet of louvered material having a plurality of generally parallel thin opaque louvers set in a transparent matrix at an angle to the faces of said sheet, said louvers being spaced with opposed edges of adjacent louvers at least contacting a single plane normal to said faces to prevent transmission of light striking said sheet perpendicular to said faces, a light source positioned to one side of said sheet of louvered material to direct light through said matrix between said louvers along paths generally parallel to said louvers, and an article to be displayed positioned on the opposed side and parallel to said sheet Of louvered material to be illuminated by radiation from said light source passing through said matrix between said louvers, said article including a differential pattern of light diffusive and transparent areas defining the indicia to be displayed and said differential pattern being at least partially of contrasting coloration to said opaque louvers so that said differential pattern is visible both from ambient light and under illumination.
Claim 2
Dependent Claim
175 words
A display device comprising: a sheet of louvered material having a plurality of generally parallel thin opaque louvers set in a transparent matrix at an angle to the faces of said sheet, said louvers being spaced with opposed edges of adjacent louvers at least contacting a single plane normal to said faces to prevent transmission of light striking said sheet perpendicular to said faces, a light source positioned to one side of said sheet of louvered material to direct light through said matrix between said louvers along paths generally parallel to said louvers, and an article to be displayed positioned on the opposed side and parallel to said sheet Of louvered material to be illuminated by radiation from said light source passing through said matrix between said louvers, said article including a differential pattern of light diffusive and transparent areas defining the indicia to be displayed and said differential pattern being at least partially of contrasting coloration to said opaque louvers so that said differential pattern is visible both from ambient light and under illumination.
Claim 3
Dependent Claim
159 words
A display device comprising: a sheet of louvered material having a plurality of generally parallel thin opaque louvers set in a transparent matrix at an angle to the faces of said sheet, said louvers being spaced with opposed edges of adjacent louvers at least contacting a single plane normal to said faces to prevent transmission of light striking said sheet perpendicular to said faces, a light source positioned to one side of said sheet of louvered material to direct light through said matrix between said louvers along paths generally parallel to said louvers, and a nematic liquid crystal display device positioned on the opposed side of and parallel to said sheet of louvered material to be illuminated by radiation from said light source passing through said matrix between said louvers, said liquid crystal display device providing a differential pattern of light diffusive and transparent areas defining the indicia to be displayed visible both from ambient light and under illumination.
Claim 4
Dependent Claim
159 words
A display device comprising: a sheet of louvered material having a plurality of generally parallel thin opaque louvers set in a transparent matrix at an angle to the faces of said sheet, said louvers being spaced with opposed edges of adjacent louvers at least contacting a single plane normal to said faces to prevent transmission of light striking said sheet perpendicular to said faces, a light source positioned to one side of said sheet of louvered material to direct light through said matrix between said louvers along paths generally parallel to said louvers, and a nematic liquid crystal display device positioned on the opposed side of and parallel to said sheet of louvered material to be illuminated by radiation from said light source passing through said matrix between said louvers, said liquid crystal display device providing a differential pattern of light diffusive and transparent areas defining the indicia to be displayed visible both from ambient light and under illumination.
Claim 5
Dependent Claim
147 words
A display device comprising: a sheet of louvered material having a plurality of generally parallel thin opaque louvers set in a transparent matrix at an angle to the faces of said sheet, said louvers being spaced with opposed edges of adjacent louvers at least contacting a single plane normal to said faces to prevent transmission of light striking said sheet perpendicular to said faces, a light source positioned to one side of said sheet of louvered material to direct light through said matrix between said louvers along paths generally parallel to said louvers, and a dark and light photographic transparency positioned on the opposed side of and parallel to said sheet of louvered material to be illuminated by radiation from said light source passing through said matrix between said louvers so that under illumination the dark and light areas of said transparency appear light and dark respectively.
Claim 6
Dependent Claim
147 words
A display device comprising: a sheet of louvered material having a plurality of generally parallel thin opaque louvers set in a transparent matrix at an angle to the faces of said sheet, said louvers being spaced with opposed edges of adjacent louvers at least contacting a single plane normal to said faces to prevent transmission of light striking said sheet perpendicular to said faces, a light source positioned to one side of said sheet of louvered material to direct light through said matrix between said louvers along paths generally parallel to said louvers, and a dark and light photographic transparency positioned on the opposed side of and parallel to said sheet of louvered material to be illuminated by radiation from said light source passing through said matrix between said louvers so that under illumination the dark and light areas of said transparency appear light and dark respectively.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-04-04 | 1975-10-04 | 1976-04-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-04 | 1979-10-04 | 1980-04-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-04 | 1983-10-04 | 1984-04-04 | $7700.00 | Window Closed / Lapsed |